I guess it's not the DAC then. The Krell was bought used from agon. After a took a shower last night and listen a bit more before bed, I didn't notice anymore fatigue.

So it's perfectly safe for class A gear to run at ~50C?

the KAV 400xi doesn't have much Class A bias. the dealer where i bought mine from years ago didn't know how much, but considered it Class A/B at least for driving speaker loads. we're talking about 200W/8ohms with some decent V-swing here, so yes, some heat through the well ventilated chassis is normal. just make sure you have at least 5" of space above the chassis and you'll be fine.

Okay, my Leben CS300 (integrated tube amp with headphone output) landed this afternoon. Allegedly it has either 800mW or 1W from the headphone output - I don't know what mine has. Anyway - I can safely say it DOES NOT drive HE-6 from the headphone output to anything more than quiet to moderate levels - then it starts to distort very clearly. When I put on the Prelude from Carmen by Bizet, it was distorting awfully. This is quite surprising to me, because even from the Balanced amp card in the HM-801 it does better (and possibly also louder).

I have to correct myself a little here: After having the CS300 for a while and testing several other tracks, it seems that the Prelude from Carmen is giving the CS300 some early distortion so to speak - that is - I can listen to other tracks louder without distortion. This is with HE-6 from headphone output. At the same volume dial position I also hear distortion on my speakers. In other words, it might have to do with a too high level at the input stage. (Maybe someone with better tech knowledge can correct me here?)

Today I mounted a couple of 10 Ohm power resistors in parallel on the speaker taps and attatched the HE-6 to those. Since the CS300 is 12W, the HE-6 receives up to 2W (and the resistor 10W). This way I have a much higher output available - higher than I need, but maybe not high enough to play distortion-free at profoundly ear damaging levels. In other words I feel I have enough power. However, I now hear a little bit of humming between tracks (and when the music is very low level). This is allegedly fixed by mounting a choke, but I won't do that myself ...

Treble is simply gorgeous and bass is tight and punchy. A very relaxed sound with lots of space around instruments.

Just wondering if anyone had any opinion on the Yamaha P2201. Its a beast of a power amplifier. I'm looking at this or something like the Pioneer SX-1010. Basically vintage powerful gear. The Yamaha is much more powerful but the SX is more of a well known high end receiver.

I can confirm that this amp can cause fatigue if you try to listen at levels slightly louder than normal. Just keep it at your normal level and it would be fine.

Do you guys have any solution for eliminating the slight background "hiss" from amps? Of the speaker amps I've owned, this one has the lowest amount of hiss, but it would be nice to completely rid of it.

And what do you guys do to keep the volume between tracks the same? I use foobar and I've applied replaygain to my entire collection, but I wonder if there are alternatives.

I can confirm that this amp can cause fatigue if you try to listen at levels slightly louder than normal. Just keep it at your normal level and it would be fine.

Do you guys have any solution for eliminating the slight background "hiss" from amps? Of the speaker amps I've owned, this one has the lowest amount of hiss, but it would be nice to completely rid of it.

And what do you guys do to keep the volume between tracks the same? I use foobar and I've applied replaygain to my entire collection, but I wonder if there are alternatives.

You could get a little resistor adapter for the amplifier. Mal put a 500 ohm pair in front of his emotiva.